1. Field of the Invention
The present invention relates to a method for manufacturing a rare earth magnetic powder having high magnetic anisotropy, and to a method for manufacturing a rare earth magnet using the rare earth magnetic powder.
2. Description of the Background
A method for manufacturing a rare earth magnetic powder is known as described in, for example, Japanese Patent Laid-Open No. 2-04901, in which an alloy material (hereinafter referred to as an R--T--M alloy material) containing at least one rare earth metal including Y (hereinafter referred to as R), Fe or an Fe component, which is partly replaced by Co or Ni (hereinafter referred to as T), and B or a B component, which is partly replaced by C (hereinafter referred to as M) as primary components, and an alloy material (hereinafter referred to as an R--T--M--A alloy material) comprising the R--T--M alloy material and 0.001-5 atomic percent of at least one element selected from the group consisting of Si, Ga, Zr, Nb, Mo, Hf, Ta, W, Al, Ti and V (hereinafter referred to as A) is homogenized, if necessary, in an Ar gas atmosphere at a temperature of 600-1,200.degree. C. The alloy material is heated 500-1,000.degree. C. in a hydrogen atmosphere or a mixed gas atmosphere of hydrogen and an inert gas and held at the specific temperature for a hydrogenation treatment. The alloy is dehydrogenated at a temperature of 500-1,000.degree. C. in a vacuum, cooled and then pulverized.
In recent years, the demand for rare earth magnetic powders having higher magnetic anisotropy than conventional powders has increased in order to achieve further miniaturization and higher performance of magnetic parts in the electric and electronic fields. No rare earth magnetic powder having sufficiently high magnetic anisotropy for these purposes has yet been obtained.